A model of interaction of Phobos’ surface with the martian environment

We simulate space weathering of Phobos’ surface due to both sputtering by solar wind ions (H+ and He2+) and planetary protons, and surface material vaporization by micrometeoroids impact. Assuming an Iron-rich composition of Phobos’ regolith, we find that densities of neutral species (Fe, O, Al, Ca, Mg, Na) in the martian environment are in the range (10−4–10−1 cm−3), and observe an ejecta disk with a radius of 6 martian radii in the equatorial plane and a thickness of 3 martian radii in the perpendicular plane. In order to determine the observability of such species from space based instruments, we also estimate their solar scattering emission line intensities. We conclude that Magnesium would be the only potential candidate suitable for spectral detection.

Research highlights► Study of the space weathering of the surface of Phobos. ► Use of a model. ► Estimate of the neutral densities within the martian environment due to surface sputtering.